Helmets for use in a variety of different sporting events, as well as for a variety of different recreational activities or non-recreational activities, are well known. The known primary purpose of these helmets is to protect a wearer's head from injury in the event that a force is directed thereat. Thus, a principal purpose of helmets is wearer safety. In fact, government and/or other standards exist that govern the performance of helmets intended for certain activities when subjected to certain forces.
Helmets used by those engaged in certain sports typically have a hard outer shell that covers some type of energy-absorbing material. The hard outer shell of most sport helmets is typically comprised of a plastic material. The outer shell typically covers an expanded inner layer that lies between the outer shell and the wearer's head. The inner layer is intended to absorb energy in the event it becomes necessary in order to minimize the energy transmitted to a wearer's head. Examples of known impact resistant materials used in the inner layer include single layer polymeric materials such as polystyrene or multiple layer polymeric materials. Alternatively, protection can be provided by a dense polyethylene outer shell that covers inner polypropylene pads capable of absorbing multiple impacts.
For non-recreational activities, the composition of the outer shell may vary. For example, the composition of the outer shell, when used for military purposes, is typically formed of polymeric or metallic material that is capable of resisting any type of ordnance, including ammunition for weapons as well as explosives or similar items. For example, one non-limiting example of a polymeric material that may form a portion of the composition of the outer shell is Kevlar®, manufactured and sold by E.I. duPont De Nemours and Company of Wilmington, Del. Alternatively, for a motorcycle helmet, the composition of the outer shell may be a hard, impact resistant polymer such as ABS (acrylonitrile-butadiene-styrene).
Regardless of the intended use, it is generally well known that current protective helmets do not provide a high degree of comfort. This is principally because the helmet itself and the inner lining are designed principally for safety purposes and not for comfort. As such they can be relatively heavy and cumbersome.
In addition, the methods for adjusting the helmet to the size of a wearer's head typically occur with adjustments in position to the outer plastic shell, and not to the inner liner. To adjust these helmets, a user typically is required to loosen adjustment screws and push or pull the outer shell manually to a desired position and retighten the adjustment screws. The helmet is then replaced onto the wearer's head to check the resizing. As one of ordinary skill appreciates, such a task is cumbersome and difficult to achieve the desired snug fit. Moreover, the sizing of the inner lining is not adjusted in these methods, thus precise fitting of the inner lining of the helmet to the wearer's head is not achieved, resulting in a loss of comfort to the wearer.
In alternative known helmets, the sizing of the helmet is achieved by changing the thickness of the foam padding contained within the inner lining. This is accomplished by replacing the inner lining completely or adding additional liner pads to existing liner configurations. The process for fitting the helmet precisely to a wearer's head, similar to the use of adjustment screws, is cumbersome. Also, it is difficult to achieve an appropriate snug fit that provides the necessary stability of the helmet on a user's head. The process is no simpler in systems that utilize adjustment screws and allow the changing of inner lining padding.
In still other helmets, the adjustment of the sizing of the helmet to the user's head is achieved through the use of straps. The straps are secured to the outer shell and one or more location and are adjusted in a wide variety of ways. The straps are typically either formed from a flexible plastic material or of a flexible non-polymeric material such as leather or the like. Each of these materials has drawbacks. For example, a hard but flexible plastic strap does not provide a high degree of comfort to a user, especially in areas wherein the strap directly contacts a user's head. Leather straps provide such a comfort, but do not provide the desired durability characteristics, especially at points wherein the strap is fastened to the outer shell.
It would thus be desirable to provide a helmet that provides an appropriate balance between wearer safety and wearer comfort. It is also desirable that such a helmet is easily adjustable.